Sealable fluid containment assembly

Abstract

A hermetically sealable fluid containment assembly is provided. Fluids, such as compressed gases, are typically stored in a base container having a shoulder with a neck projecting outwardly from the shoulder. In accordance with the invention, a collar member generally surrounds the neck and rests upon the shoulder of the base container. A locking arrangement is provided to securely fasten the collar member to the base container. A closure member in the form of a protective cap engages the collar member. To prevent the leakage of fluid between the collar and the base container, a seal is provided between respectively engaging surfaces of the base container and the collar. The leakage of gas between the collar member and the closure member is also prevented by a second seal disposed between respective engaging surfaces of the closure member and the collar member.

What is claimed is: 
     
       1. A hermetically sealable fluid containment assembly comprising: (A) a base container having a generally hollow interior for the containment of fluids, the base container having a shoulder portion and a neck portion projecting outwardly from the shoulder portion to provide an opening for the container, the shoulder portion having an outer abutment surface encircling the neck portion;   (B) a collar member encircling the neck portion and having a shoulder-engaging surface generally conforming to the shape of the abutment surface of the shoulder portion for engaging and mating with the abutment surface, the shoulder-engaging surface being configured to provide a surface area of contact between the shoulder-engaging surface and the abutment surface sufficient to distribute stresses away from the neck and to reduce stresses tending to separate the collar member from the base container, said collar member portion having an outer contact surface with an opening providing access to the opening for the container;   (C) locking means for securely fastening the collar member to the base container;   (D) first sealing means disposed between a portion of the shoulder-engaging surface of said collar member and a portion of the abutment surface of the shoulder portion for sealing the collar member with the shoulder portion;   (E) a closure member for sealably closing the opening into the base container, the closure member having a collar-engaging portion for engaging the collar member for use in retaining the closure member on the collar and having a collar-engaging surface generally conforming to the shape of the contact surface of the collar for engaging and mating with the contact surface and configured to provide a surface area of contact between the collar-engaging surface and the contact surface sufficient to reduce stress tending to separate the closure member from the collar member; and   (F) second sealing means disposed between a portion of the collar-engaging surface of the closure member and a portion of the contact surface of the collar member for sealing the closure member with said collar member so that the opening into the hollow interior of the base container is hermetically sealed.   
     
     
       2. The assembly set forth in claim 1 wherein said neck is generally tubular and the locking means comprises a generally cylindrical threaded outer surface on the neck portion and a generally cylindrical threaded inner surface on the collar member adapted to mate with the threaded outer surface of the neck so that the collar member screws onto the neck to securely fasten the collar member to the base container. 
     
     
       3. The assembly set forth in claim 2 wherein the locking means further comprises a lock nut having a generally cylindrical threaded inner surface adapted to mate with the threaded outer surface of the neck so that the locking nut screws onto the neck and engages the collar member to lock the collar member into position on the neck. 
     
     
       4. The assembly set forth in claim 1 wherein said neck is generally cylindrical and has a threaded portion around its outer end, the locking means comprising a lock nut having a generally threaded inner surface adapted to mate with the threaded portion of the neck so that the locking nut screws onto the neck and engages the collar member to lock the collar member into position on the neck. 
     
     
       5. The assembly set forth in claim 1 comprising holding means engageable with the closure member and the collar member for locking the closure member in sealed position with the collar member. 
     
     
       6. The assembly set forth in claim 5 wherein the holding means comprises at least one set screw and the closure member includes at least one threaded passageway extending through the closure member into communication with the collar member so that the set screw is insertable into the threaded passageway to engage the collar member to lock the closure member in sealed position with the collar member. 
     
     
       7. The assembly set forth in claim 1 wherein said collar member is generally annular in shape and includes a threaded generally cylindrical outer surface and wherein said closure member comprises a mating generally cylindrical threaded inner surface to mesh with the threaded outer cylindrical surface of the collar member so that the closure member screws onto the collar member. 
     
     
       8. The assembly set forth in claim 7 comprising holding means for locking the closure member into screwed position on the collar member. 
     
     
       9. The assembly set forth in claim 8 wherein said holding means comprises at least one set screw and the closure member includes at least one threaded passageway extending through the closure member into communication with the collar member so that the set screw is insertable into the threaded passageway to engage the collar member to lock the closure member in sealed position with the collar member. 
     
     
       10. The assembly set forth in claim 9 comprising a deformable member insertable into the threaded passageway intermediate the set screw and the threaded outer cylindrical surface of the collar member to generally deform to the shape of the threaded outer cylindrical surface of the collar member to prevent damage to the threaded outer surface of the collar member when the set screw locks the closure member with the collar member. 
     
     
       11. The assembly set forth in claim 1 wherein the closure member includes a generally hollow interior cavity and the collar-engaging surface is recessed a distance into the hollow interior cavity of the closure member. 
     
     
       12. The assembly set forth in claim 1 wherein the collar-engaging surface of the closure member and the contact surface of the collar member are generally planar to abut one another. 
     
     
       13. The assembly set forth in claim 12 wherein the collar-engaging surface and the contact surface are generally annular in shape. 
     
     
       14. The assembly set forth in claim 13 wherein one of the collar-engaging surface and the contact surface includes a generally annular recess disposed between the collar-engaging surface and the contact surface and wherein the second sealing means comprises an O-ring seal disposed in the recess having a thickness greater than the depth of the recess so that the O-ring seal is compressed within the recess to form a seal between the collar-engaging surface and the contact surface. 
     
     
       15. The assembly set forth in claim 14 wherein the recess is provided on the collar-engaging surface of the closure means. 
     
     
       16. The assembly set forth in claim 1 wherein the collar-engaging surface of the closure member and the contact surface of the collar member are configured to provide the surface area of contact therebetween sufficient to reduce stresses between the closure member and the collar member produced by external forces acting on the closure member. 
     
     
       17. The assembly set forth in claim 1 wherein said shoulder-engaging surface of said collar member and the abutment surface of the shoulder are generally frusto-conical in shape. 
     
     
       18. The assembly set forth in claim 17 wherein one of the shoulder-engaging surface and the abutment surface includes a generally annular recess disposed between the shoulder-engaging surface and the abutment surface and wherein the first sealing means comprises an O-ring seal disposed in the recess having a thickness greater than the depth of the recess so that the O-ring seal is compressed within the recess to form a seal between the shoulder-engaging surface and the abutment surface. 
     
     
       19. The assembly set forth in claim 18 wherein the recess is provided in the shoulder-engaging surface of the collar member. 
     
     
       20. The assembly set forth in claim 1 wherein the shoulder-engaging surface of the collar member and the abutment surface of the shoulder are configured to provide the surface area of contact therebetween extending from a base end of the neck outwardly along the shoulder to reduce stresses on the neck produced by external forces acting on the closure member. 
     
     
       21. The assembly set forth in claim 1 wherein said first sealing means is disposed between an intermediate portion of the shoulder-engaging surface and an intermediate portion of the abutment surface, said shoulder-engaging surface and said abutment surface being configured to provided said surface area of contact therebetween on opposite sides of said first sealing means. 
     
     
       22. The assembly set forth in claim 1 wherein said second sealing means is disposed between an intermediate portion of said collar-engaging surface and an intermediate portion of said contact surface, said collar-engaging surface and said contact surface being configured to provide said surface area of contact therebetween on opposite sides of said second sealing means.